Method of tamping the ballast of a railway track and device for the execution of this method



June 22, 1965 P. GROSSMANN METHOD OF TAMPING THE BALLAST OF A RAILWAY TRACK AND DEVICE FOR THE EXECUTION OF THIS METHOD Filed Feb. 1, 1963 E 2 Sheets-Sheet l June 22, 1965 P. GROSSMANN 3,190,234

METHOD OF TAMPING THE BALLAST OF A RAILWAY TRACK AND DEVICE FOR THE EXECUTION OF THIS METHOD Filed Feb. 1, 1963 2 Sheets-Sheet 2' United States ate v METHOD OF TAMPING THE BALLAST OF A RAE- WAY TRACK AND DEVICE FOR THE EXECU- TION OF THIS METHOD Paul Grossmann, Lausanne, Switzerland, assignor to Matisa Materiel Industriel S.A., Lausanne, Switzerland, and Constructions Mecaniques S.A., Renens, Vaud, Switzerland, bothcorporafions of Switzerland Filed Feb. 1, 1963, Ser. No. 255,605 Claims priority, application Switzerland, Feb. 8, 1952, 1,570/ 62 13 Claims. (Cl. 104-12) At the present time numerous types of tamping machines for tamping the ballast under the ties of railroads are known. The ballast is brought andjpacked under the ties by the action of the tamping tools, and compression is obtained by the closing of two opposed tools of appropriate form or of a certain number of pairs of opposed tools acting one on each side of a transverse section of the ties, the closing and the opening of said tools being obtained by mechanical devices or the action of a fluid under pressure, the tamping tools moreover being moved simultaneously by .a closing movement and a vibrating movement having the effect of imparting to the ballast a certain compactness.

The tamping speed particularly depends, apart from :frequency of the vibrations of the tools, on the amplitude of these vibrations.

It has been noted that too large an amplitude can cause, particularly at the end of the closing movement of the said tools, either damage to these tools or to its control means as a consequence of overload thereof. Moreover, too large an amplitude can cause lifting of the ties and'of the rails as a consequence of too great a compacting of the ballast Which-upsets the levelling of the track.

Too large amplitudes of vibration of the tools can also provoke a reseparation of the ballast anddestroy the compacting already efiected.

The present invention has as an object to provide a method and a device for tamping the ballast of railway track by means of at least one pair of tamping tools vibrating and closing during the tamping operation, which are free from the objection mentioned above.

The method according to the invention is characterized in that the amplitude of vibration of the tamping tools is varied so that it is less at the end of the working stroke than at the beginning of the working stroke.

The device according to the invention for the execution of this method is characterized in that it comprises a symmetrical knuckle-mechanism pivotally connected at its ends to the levers supporting the tamping tools, and centrally to a vibrator acting in the direction of the axis of symmetry of the knuckle mechanism. The knuckle mechanism is constituted by a pair of bars connected at their ends to a common pivot. The device further comprises means for displacing the knuckle mechanism at the location where the vibrator is connected in the direction of the axis of symmetry while the tools are closing to diminish the amplitude of the vibrations of the tools as the tools close during their working stroke.

The accompanying drawings represent schematically and by Way of example five embodiments of apparatus according to the invention, wherein FIGS. 15 respectively correspond to a different embodiment.

In the different figures, the mobile chassis to whichvthe tamping device is fixed, is represented schematically by a rectangular chain dotted outline, and a vibrator V is provided which is adapted for producing vibrations. AB and AB represents two bars of a knuckle-mechanism, having a hinged connection at the mid-point at pivot A 3,l% ,234 Patented} June .22, 19.65

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which receives directly or indirectly the vibrations produced by the vibrator V along an axis of symmetry of the said mechanism passing through the point A. The two bars AB, AB are arranged symmetrically with respect to thisaxis.

In the embodiment of FIG. 1, B and B are the end points of the bars AB and AB, respectively, at opposite sides of the hinged connection or joint A, and to which are hinged the two levers BCE and B'C'E'. The latter levers respectively are supported at pivot C and pivot C respectively, which are fixed with respect to the mobile chassis and which support each a tamping tool D, and D respectively.

Suitable expandable and contractable means such as a jack X is supported on the mobile chassis and serves to displace the point A in either direction along a line coincident with the symmetry axis of the tamping device. A" indicates the position of the connecting point A of the two bars AB and AB. at the moment when these two bars are perpendicular or nearly perpendicular to the symmetry axis, that is in alignment on a straight line DAB'. M is a guide for the joint A extending along the axis of symmetry of the tamping device, thereby constraining vibratory movement of joint A from vibrator V to be in the same direction as the stroke of thejack X.

oz is the angle defined by the bars AB and AB on the side of the connection point A at whichthe tamping tools D and D' are situated. This angle may be greater or smaller than or may be exactly this value. The rectangle F represents the cross section of a' single tie of the track.

The vibrating system is constituted by the vibrator V having a substantially constant amplitude of vibration and the two bars connected at their point A. The vibrator and bars are shown in the same plane as the tool supporting lever, but the plane comprising the said vibrating system can also differ from that which contains the tool supporting lever.

The bars connected at their common point A, form, with regard to the transmission of any shifting movements of the said joint A in the direction of the symmetry axis of the camping mechanism to the tool supporting lever, a knuckle mechanism which permits the varying of the amplitude of the'vibration movements of the tool supporting levers as a function of the position of the joint A and, in consequence, of the angle or included between the said two bars at the joint A. In particular, the vibrating movements imparted to the joint A by the vibratorV in the direction indicated produces an angular oscillation of the levers B,C,E, BC'E' about the join-ts C,C' respectively, to cause'the tools D,D' to vibrate in the example according to FIG. 1. The angular amplitude of this oscillation of levers BCE, B'CE depends on the value of the angle a, the said amplitude becoming virtually zero when the angle a equals 180, even though the vibrator V produces vibrations of finite amplitude. Thus, irrespective of the magnitude of the amplitude of the vibrator V, the levers B,C,E, BCE' are substantially at rest when the angle or is 180. Thus, the tools D,D' will not be subject to vibration when oz=180.

In fact, as the joint A approaches the positionin which a=180' during the stroke of jack X, the amplitude of vibration of the tools is being reduced. Consequently,

amplitude of the vibrations transmitted to these tools dur-' ing the working stroke of the latter. 1

In the other embodiments the same reference letters as in the FIG. lhave' been used to designate elements which are similar to those of this figure.

FIG. 2 represents an embodiment in'which the opening and closing movement of the tools is produced by a jack Wacting on the tool supporting barsina direction perpendicular to the symmetry axis of the knuckle-mechanism. In this case, the jack does not'follow the move.-

ments of the knuckle-mechanism, however, it determines the movement of the mid-connecting pivot A along the guide M, by means of the separation and of the approaching of the ends B, B of the said mechanism. It is im portant that the bars AB, AB do not completely fall into line at the end of the Working stroke,in order to avoid a locking of the tools. The angle on will, therefor, remain in this case slightly below 180.

Here again as in the embodiment in FIG.;2, there is provided means (jack W) which produce the closing and opening of the tools, and also the variation of the amplitude of the vibrations of the tools. j a i In the embodiment shown in FIG. 3, as in the e'mbodi ment in FIG. 1, a jack is provided which produces simultaneously the closing and opening movements of the tools and the diminution: of the amplitude ofthe vibrations], transmitted to the tools during the working stroke of the latter. But here, the device is adapted to tamp theballast at will under single ties For under double ties G.I To

7 place, the movement of thej mobile. chassis causing the rotating fly-wheel, or by of the vibrations is effected by a knuckle-mechanism.

If there are on the same machine a number'of pairs of tamping tools, all of these pairs of tools or part of them may be controlled by the ,same device, such as those which have been described. The tools and the whole or part of their control device are then fixed on one or more t mobile chassis in a sense perpendicular to the ,plane formed by the track at the point where the tamping takes descent of the tools into the ballast at the beginning of the tamping operation, and the rising of the said, tools I at the end of the said operation. The closing and open-: ing of the tools of the same pair may be controlled either by the pressure of the tamping tools on the ballast, or by a mechanical or electric limitation of their stroke;

The devices described have the following'advantages:

The rate of variation of the amplitude of the vibrations of the tamping tools may be adjusted within certain this effect it is provided with the following additionalv means;

An apparatus schematically indicated at R, which allows a symmetry axis of the tamping device;

A double device T, T, which allows a variation of the length of the two bars 'AB, AB'.' f i In the embodiment shown in FIG. 4, the means for closing and opening the tools is represented at S whereas the 7 means for varying the amplitudejof'the vibrations transmitted to the tools is indicated at Q. These means respe'c;

tively areftwo jacks each acting independently of the other, the first,'S, acting on the bars BE, B'E' and in a di rection perpendicular to the symmetry axis of the knuckle mechanism, the second, Q; acting in the direction of the axis of symmetry.

limits, either with the machine at rest, or during the tamping cycle;

hydraulic or electric vibrating 1 systems, or by electronic devices, are not transmitted 1 directly to the tools nor to the. levers to which the latter, can be fixed ,by any suitable means, but the transmission" The vibration amplitude of the tamping tools is vir tually zero when the distance between the said tools of a.

same 'pair of tools has; reached a determined value at the end of the closing movement;

' The variation of the vibration amplitude of the;

tools may be made dependenton the space between the said,

tools of a same pair; V a

The variation of the vibration amplitudesof, the tools of each pair, or of the different pairs of tools forming part of the same machine, may be controlled indirectly by the reaction-pressure of the ballast against the tamping tools during their closing movement; I

Thevariation of the vibration amplitudes of the tamping tools may be .controlled independently of the space between the said tools.

7 tages mentioned at the beginning of operation of the In this embodiment, the tool'supportingbars BE and BE pivot, when the tools. are closing, about the joints C and C. The knuckle-mechanism ACC' is, in this case, connected ,to the tool supporting levers at the joints C and C which generally remain fixed for the closing movement. These joints C, C are merely displaced to the extent of the vibrations imparted to 'the joint A by the vibrator V. The amplitude of these vibrations can be modified by shifting the end position of joint A. Therdevice Q is utilized for that purpose. It may becontrolled by known means which are'not shown in the drawings, in dependence on the position of the'tools,.as for example by means of check-switches. The displacements of the pivoting joints C and C can be compensated by means of the closing jack S which adjusts the position of joints B, B'.- s V The last embodiment shown in FIG. 5 differs from that of FIG. ,4 only by the fact that'additional means T,

.T' are provided for adjusting the length of thebars AC, AC of the knuckle-mechanism, in order to keep the points; C, C in position, when the ballast is to be'tamped under one single tie F, or undera double tie G.

It should be noted that the advantage of varying the amplitude of the vibrations of the tools, during the working stroke of the latter, results from thefollowiug The devices described allow avoiding the disadvantamping machines in which the tools are subjected to forced vibrations.f They avoid also the disadvantage in tamping machines in which'the tools are moved by free i vibrations wherein the penetration of the tools into the ballast and its compacting are shown by reason of the fact that the vibration amplitude of the tools diminishes as soon as they are subject to the reaction-pressure of the.

ballast. It is'obvious that this is'not' the case with the devices described by reason of thefact that the vibration amplitude of the tools isalways well defined and under control for any position of the tools.

' What I claim is:

1. Atamping device for tamping the ballast ofa rail- Way track, said device having at least one pair of tampr 7 ing tools adapted for-being displaced relative to one an-' other while undergoing vibration during a working stroke in a tamping operation, said device comprising: pivotally fact which is evident from theembodiments described: the

' vibrating movements obtained by a-mechanical vibratingsystem, such as an eccentric or an out of balance device,

supported levers supporting the tamping tools, jack means] connected to said levers for producing said Working stroke, vibration means having a constant amplitude of. vibration for vibrating the levers and the tools therewith, and means pivotally connected to the levers and to the. vibration means to pivotally move the levers and cause. the tools to be vibrated relative to one another :while modifying the amplitude of the vibration transferred tothe tools such that the latter undergo reduced amplitude of vibration as the tools are displaced towards onelanother in a Working stroke;

2. A tamping device for tamping'the'ballastof a rail: way track, comprising a pair of levers having'opposite ends, pivots supporting said levers intermediate the ends 7 thereof for pivotal movement aboutifixed axes, a tamping tool on each lever, a pair of symmetricalbars each pivotally connected to a respective lever, a pivot con-"- necting the bars together in symmetrical fashion, a vibrator having a constant amplitude of vibration connected to the latter pivot to vibrate the same and the bars there with along a line coincident with an axis of symmetry of the bars, and jack means for displacing the pivot which connects the bars along the axis of symmetry of the bars to cause said bars as a result of the displacement of the pivot to be rotated and thereby cause the levers to undergo rotation, the tools being displaced relative to one another by the movement of said levers While simultaneously the tamping tools are caused to vibrate with an amplitude which is a function of the relative angular relation of the bars.

3. A tamping device for tamping the ballast of a railway track comprising a pair of symmetrical pivotally supported levers having opposite ends, a tamping tool at a corresponding end of each lever, a pair of bars symmetrically connected to the levers remote from the tamping tools, a pivot connecting said bars together, guide means supporting said pivot for displacement along a line which is symmetrical with respect to said bars and levers, a vibrating device having a constant amplitude of vibration connected to the pivot to vibrate the same along said symmetrical line and jack means for displacing the pivot along said line to rotate said bars and in turn rotate said levers to thereby displace the tools relative to one another while simultaneously said tools undergo vibration as a result of the vibrations of the vibrating device at a magnitude which diminishes as a function of the displacement of the pivot. V

4. A tamping device for tamping the ballast of a railway track, said device comprising at least one pair of tamping tools adapted for vibrating and closing during a working stroke in a tamping operation, levers supporting the tamping tools, means defining a symmetrical knuckle mechanism pivotally connected to the levers supporting the tamping tools, a vibrator device connected centrally to the knuckle mechanism and acting along the axis of symmetry of the mechanism to transfer vibration of said tools via said mechanism and said levers and jack means operatively associated with the knuckle mechanism for displacing the same at the location where the vibrator device is connected to the knuckle mechanism to diminish the amplitude of the vibrations of the tools as the tools close during their working stroke.

5. A device according to claim 4 wherein the knuckle mechanism includes a pair of bars and a central pivot connecting said bars together, said pivot being movable.

between a first extreme position in which the bars define therebetween a certain minimum angle, and a second extreme position in which the bars define therebetween an angle of approximately 180, at which position substantially no vibration is transmitted to the tools.

6. A device according to claim 4 comprising second jack means connected to said levers for opening and clos ing the tools in said working stroke and wherein the first said jack means for moving the knuckle mechanism is independent of the second jack means for opening and closing the tools.

7. A device according to claim 4 wherein the jack means for moving the knuckle mechanism also constitutes means for providing said working stroke for opening and closing the tools.

8. A device according to claim 4 comprising second jack means for opening and closing the tools connected to the levers supporting the tools, and including an extendable and contractable jack member extending in a direction perpendicular to the axis of symmetry of the knuckle mechanism.

9. A device according to claim 4 comprising means hinged to the levers supporting the tools at two symmetrical locations of the latter for adjusting the relative position of the tools in the closed position of the tools.

10. A device according to claim 4 wherein the knuckle mechanism includes a pair of bars each respectively including means for adjusting the length of the particular bar.

7 11. A tamping device for tamping the ballast of a railway track, said device comprising a pair of tamping tools, a lever supporting each tool, means symmetrically supporting said levers with respect to an axis of symmetry for pivotal movement towards one another during a closing stroke of the tools, vibrating means having a constant amplitude of vibration directed along said axis ofsymmetry, means guidably supporting said vibrating means for displacement along said axis of symmetry and means connecting the vibrating means and said levers to displace the vibrating means and pivotally move the levers therewith in associated relation and simultaneously vary the amplitude of vibration applied to the tools in relation to the relative position of the levers whereby the amplitude of vibration of the tools may be gradually diminished during the closing stroke of the tools.

12. In a ballast tamping machine: a pair of tamping tools, a lever supporting each tool, means symmetrically supporting said levers with respect to an axis of symmetry for pivotal movement towards one another during a closing stroke of the tools, a knuckle mechanism including a pair of rods and a pivot connecting said rods together, means coupled to said pivot for vibrating the same in constant amplitude along said axis, said knuckle mechanism being connected to said levers to. transmit vibration thereto, guide means located along said axis of symmetry guidably supporting said pivot for displacement along said axis, andrmeans for displacing the pivot along the guide means to'cause pivotal movement of the levers during the closing stroke to vary the amplitude transmitted to the levers in relation to the position of the levers whereby the amplitude of vibration of the tools may be gradually diminished during the closing stroke of the tools.

13. A method of tampingthe ballast of a railway track by means of at least one pair of tamping tools, said method comprising moving the tools towards one another during a tamping operation, vibrating the tools while moving them towards one another, and varying the amplitude of vibration of the tamping tools as the tools move towards one another to cause the tools to undergo gradually diminishing amplitude of vibration as the tools move towards one another.

References Cited by the Examiner UNITED STATES PATENTS FOREIGN PATENTS 8/61 Austria.

1/56 Germany.

EUGENE G. BOTZ, Primary Examiner.

LEO QUACKENBUSH, Examiner. 

1. A TAMPING DEVICE FOR TAMPING THE BALLAST OF A RAILWAY TRACK, SAID DEVICE HAVING AT LEAST ONE PAIR OF TAMPING TOOLS ADAPTED FOR BEING DISPLACED RELATIVE TO ONE ANOTHER WHILE UNDERGOING VIBRATION DURING A WORKING STROKE IN A TAMPING OPERATION, SAID DEVICE COMPRISING: PIVOTALLY SUPPORTED LEVERS SUPPORTING THE TAMPING TOOLS, JACK MEANS CONNECTED TO SAID LEVERS FOR PRODUCING SAID WORKING STROKE, VIBRATION MEANS HAVING A CONSTANT AMPLITUDE OF VIBRATION FOR VIBRATING THE LEVERS AND THE TOOLS THEREWITH, AND MEANS PIVOTALLY CONNECTED TO THE LEVERS AND TO THE VIBRATION MEANS TO PIVOTALLY MOVE THE LEVERS AND CAUSE THE TOOLS TO BE VIBRATED RELATIVE TO ONE ANOTHER WHILE MODIFYING THE AMPLITUDE OF THE VIBRATION TRANSFERRED TO THE TOOLS SUCH THAT THE LATTER UNDERGO REDUCED AMPLITUDE OF VIBRATION AS THE TOOLS ARE DISPOSED TOWARDS ONE ANOTHER IN A WORKING STROKE. 